As the cloud finished spreading and killing the useless and weak, Mei quickly made her nineteen shadow clones create steam clones because shadow clones wouldn't be able to survive in the cloud. She enwrapped herself in a protective layer of suiton chakra, creating a soft, almost invisible blue aura around her body, and with the newly created nineteen steam clones, she rushed into the white searing steam cloud of death while her shadow clones popped out of existence, much to her relief returning her quite a bit of chakra. Mei used a whole lot to create the first attack and despite having what Rei proudly dubbed as reserves of an almost jinchuuriki, thanks to his brutal training, Mei was quite exhausted. Getting the chakra from the clones gave her much needed second wind.
She was aware she had every advantage over her enemies. They were scared, demoralized, trapped in a cloud where visibility was as good as nill. The cloud also made them use their chakra, forcing them to effectively albeit a bit slowly burn through their reserves if they wanted to stay un-melted. On the other hand, she was still alone and there were hundreds of them. She had to be careful.
Mei could have waited until the enemies wasted more of their chakra but she didn't want the Iwa ninjas to find out a weakness in her Jutsu, especially since these were Iwa ninjas and the cloud was already starting to very slowly disperse. She decided to charge into it and made her clones also engage in combat with the remaining enemies.
She couldn't go and face four hundred men head-on. That would be suicide. Thankfully, there was a thick smoke-screen... It was time to act like a true Kiri ninja and use the silent killing technique she was forced to learn in the academy and later by Rei and Konan who brutally beat its mastery into her. Not that she complained. That single skill was something for which she would be eternally grateful to Rei and Konan.
Rushing through the white cloud with her eyes closed, Mei could hear the sound of starting battles as her steam clones started engaging their targets. She didn't need her eyes to fight nor could she even use them in such a thick cloud. Instead, Mei relied on her own albeit a bit limited, but still incredibly useful chakra sensing ability to sense her own chakra. The cloud was, after all, saturated with the stuff, and with just a bit of focus, Mei had an overview of the positions of every enemy of hers in the thick cloud. Well, figures. If it has a humanoid shape and is not full of her chakra, it was obviously an enemy. Locking on at the closest one, Mei charged at the ninja.
Mei felt herself being barely two meters away from her first target, happy he didn't notice her yet thanks to how silent she moved. The poor sap was confusedly looking around, not knowing what to do so Mei decided to make a quick work of him. Pulling out a kunai, she swiftly leaped at the man and buried it up to the handle into his neck, severing the spine while also supporting the dying body in order to prevent it from loudly falling to the ground. 'Damn, no sensing capabilities nor any honed instincts? This must have been one of the better genins made from the slaves.' Mei disappointedly thought as she slowly and carefully laid the body on the ground, making sure she did it as silently as possible before dashing onwards to her next target.
Mei found a gathering of five ninjas who had the sense to group up in the mist. She started molding her chakra and with just one one-handed seal, she spitted out a blob of lava while thinking, 'Lava Release: Lava Bullet.'
Contrary to her expectations, the five ninjas noticed her attack and jumped away, making the Lava Bullet impact only an empty ground. This also made the ninjas aware of Mei's position and she suddenly found herself evading two taijutsu practitioners who cracked the ground every time they impacted it.
'Thank God for Rei's agility exercises and Konan's Territory evasion course.' Mei idly thought as she sidestepped yet another haymaker of one Iwa shinobi and ducked under a right hook aimed at her chin from the other. 'These two must be chunin.' She noted before her senses flared and Mei quickly smashed her palm into the ground.
"Earth Release: Earth Wall!" Mei whispered... a testament of how surprised she was since Konan made sure to instill into her doing Jutsu silently and not say the names like some mentally-challenged idiot.
A wall of the earth with a semi-circular shape quickly appeared in between Mei and the two taijutsu-using Iwa ninjas, continuing all the way to cover her right side just a second before the wall there was impacted by Two Earth Bullets and one Fireball Justus. The three remaining ninjas from the group of five clearly could pinpoint her location by using sound. 'Tsch, just my luck, running into an experienced group.' Mei clicked her tongue.
Fortunately for Mei, the impact cracked her Earth Wall which sent some debris in the direction of the two taijutsu chunins due to the circular shape of the Earth Wall. Mei used this slight distraction and the fact they couldn't see her to her advantage and performed yet another Jutsu.
'Water Release: Cutting Blast of Finger-Doom.' She thought, again embarrassed at the naming sense of her younger self while gathering a small blob of water on her index finger. She shot the small blob of heavily condensed water straight through her Earth Wall, running it through the heart of one of the chunins, killing him instantly. The second one didn't even have time to notice his comrade's untimely demise when he found himself having the same fate.
Relaxing, Mei released a relieved sigh when her senses noted the three remaining ninjas of the group were just ambushed by one of her steam clones who just materialized in their midsts. Two were already dead due to the clone touching them which increased the concentration of the steam cloud, momentarily getting through their chakra cloaking. This made them shriek in pain and interrupted their defenses against the cloud in the surroundings, hence, melting them entirely. The last from the group was desperately trying to avoid the clone but suffered from numerous burns on his body since his control was far better than his comrades and he was able to keep his chakra cloaking... Mei didn't care enough to go and personally finish him off. The clone would have to suffice. The man was almost out of chakra anyway.
"That said, I am very low on my chakra too..." Mei dejectedly said as she kneeled on one knee to take a slight breather. 'Worse yet, while my own suiton cloaking is very cheap, due to my depleted reserves I can't really use much ninjutsu as I need the chakra. Hah~, ninjutsu specialist unable to cast ninjutsu... Is this Rei's way of telling me to not slack off in taijutsu training?' Mei dryly thought as she tracked another target with her senses, assessing the situation. '320 enemy ninjas remaining... My clones already killed more than seventy of them, huh? Well, no wonder since they can just materialize and dematerialize while killing people by just disrupting their chakra cloaking.' Mei hummed in satisfaction. Steam Clones in the middle of a searing steam cloud... so far, this was her best ninjutsu combination. She totally didn't try to emulate Rei's Kirigakure no Jutsu and Earth Clones. Nope... not at all.
After five minutes of resting, Mei stood up with a quiet groan, gleefully noting that during her rest, her clones reduced the enemy numbers to 290. She would have rested more if only Konan and Rei weren't watching her. She had no doubt they knew exactly what was going on in the steam cloud as not once during the practice did this Jutsu even slow them down. Preparing her weaponry, Mei started hunting solo prey in the thick cloud, aiming to reduce the numbers for now.
Leaping, she slit the throat of an unsuspecting boy, no older than fifteen.
'280 remaining.'
Throwing shurikens at a duo of Iwa ninjas, Mei luckily hit the throat of one while the second managed to deflect the projectiles only to be run through with a tanto Mei picked up from one corpse before she sheathed it and threw it away as the man's body fell onto the ground.
'250 remaining.'
Mei was pleased with the efficiency of her clones as she attacked yet another slave genin by using Rei's trick of latching a barely visible chakra string onto the victim's foot and tripping him. Needless to say, the thirty-year-old woman had no time to react before her spinal cord was severed, Mei already sprinting away, leaving the immobile woman to die from the steam.
'220 remaining.'
Her chakra started to be slowly replenished but Mei still didn't use any ninjutsu as she knew those who fell were the weakest sort and she would most likely need her chakra later for the stronger opponents. Especially the sole S-ranker, Kitsuha. She avoided him like a plague in the cloud and always kept her senses on him. Luckily, the man was completely disoriented and ran circles as his vision was impaired.
'Thankfully he has no chakra sensing capabilities... how disappointing.' Mei thought with an amused chuckle as yet another slave genin of Iwa fell to her kunai. '200 remaini-'
Mei was suddenly forcefully pulled back, making her eyes widen as a chill went through her spine when she saw a sword cleave the place where her head was just a second ago. From the corner of her eye, Mei noticed a barely visible thread connected to her back and sighed in sincere relief, inwardly thanking Rei for watching out for her. She didn't sense the attack at all!
'I got too cocky.' Mei scolded herself, completely aware this would give Konan enough ammunition to tease her for weeks... worse yet, this meant her training will be most likely painfully increased. 'Fuck...' She thought in resignation as she for the first time since she entered the mist, opened her eyes and melded back into the steam, using Silent Killing footsteps to move around in order to prevent being jumped again.
Chakra sensing was not giving her any feedback so Mei had to rely on her other senses in this fight. Using a small trick taught to her by Rei, Mei channeled chakra into her eyes, ears, and nose, improving her senses ten-fold. It was only then her nose scrunched as she caught a peculiar aroma with it.
"So it is the second-in-command of Kitsuha. Guess you are not just a prostitute then..." Mei quipped, making sure to make the steam around distort her voice so it was impossible to tell where it came from.
"Any you are that small brat. Who would have thought Downpour is raising yet another little army-killing monster." A sarcastic feminine voice resounded from the surroundings, also distorted. "I am going to kill you, brat."
"I wonder about that, slut. You should have stayed with what you know best. Being fucked by your superior." Mei lightly said and slightly smiled to herself when she felt the incredibly small angry fluctuation of chakra a few meters away to the left. Unfortunately, it was so short Mei didn't manage to react in time before it entirely disappeared from her senses, no doubt her opponent already gone from that spot.
"When the son of your Kage tells you to bend over and raise your ass up so he can get better access, you listen or you die." The woman's apathetic voice resounded from the surroundings, trying to sound as indifferent as possible but Mei caught the slight venomous undertone in it.
'A bit more, then...' Mei thought deviously. "Oh, if Rei told me that, I would be the happiest woman in the world. I wouldn't mind being used like that by my Master! Wagging your butt for a worthy man must be really fun!" Mei cheerfully exclaimed, making sure to bleed all of her sincere feelings into that statement while making it obvious she mocked the woman and the way she was treated by Kitsuha.
"Good try..." A quiet rageful whisper entered Mei's ears from the steam cloud, sounding almost sorrowful. "Your words won't force me to reveal my position, young assassin of Kiri. You are good. I admit that. Even I, one of the best Iwa assassins, can't locate you in this thick cloud of steam. I guess it's time to call the big guns." The resigned voice of the woman resounded with a sigh and Mei's eyes widened as she suddenly felt a big fluctuation of chakra from her right. Mei quickly snapped her wrist in that direction, throwing a kunai there but her answer was only a loud 'clang' before her lips stretched into a smile as a loud 'boom' resounded.
'Explosive tags, bitch.' Mei smirked as she felt a slight recoil in the now visible chakra, signifying the woman was injured. Her lips however set into a frown as the chakra of the woman yet again disappeared from her senses before she could pounce on the woman. "... Fuck this shit. She got away again." Mei muttered in irritation before her senses caught one important detail.
'Oh... so the slut fluctuated her chakra to alert Kitsuha.' Mei wanted to scream in agitation to the heavens. The man she avoided like plague was now hurling towards her position at break-neck speed. 'Guess this is unavoidable now. And the bitch is still hidden somewhere around... jeez, this will be a major pain in the ass, won't it?' She sighed as she checked how much chakra has been regenerated and mentally recalled the five closest of her steam clones to her position.
Mei could only chuckle bitterly at the unfairness of it all. "Time for the boss fight, then..."